#include <stdlib.h>
#include <stdio.h>
#include <string.h>

void verifica_sexo (char *str)
{
    char* aux;
    
    aux = str;
    
    if (str[0] == ' ')
	{
	    str = aux;
	    return;
	}
    if (str[0] == 'M' || str[0] == 'm')
	{
	    str = aux;
	    return;
	}
    if (str[0] == 'F' || str[0] == 'f')
	{
	    str = aux;
	    return;
	}
    else 
    {
	printf ("campo sexo invalido\n");
	str = aux;
	return;
    }
}

int main ()
{
    char nome[] = "!";
    verifica_sexo(nome);
    return 0;
}